Preparation of porous ceramics with waste zeolites as raw material

ABSTRACT

Nepheline porous ceramics with improved strength and well thermal insulation performance were synthesised at 850–1000°C by a foam-gelcasting technology, using waste zeolite powders, triethanolamine lauryl sulphate and xanthan gum respectively as the starting materials, foaming agent and gelling agent. The effect of sintering temperatures and solid contents on the physical and thermal properties of final samples were investigated. The strengths of foams increased with the firing temperatures and solid levels, and the sample possessing the porosity of 71.9% exhibited the highest compressive strength of 2.9 MPa ¹, respectively. Moreover, the one with a solid content of 20 wt-% and fired at 950°C containing 76.9% porosity and having compressive strengths respectively of 1.8 MPa showed the lowest thermal conductivity of 0.10 W/(m ^oC) at 25°C, suggesting that as-prepared porous ceramics could be potentially used as a good thermal insulation material.

KEYWORDS:

• Waste zeolite
• porous ceramics
• thermal conductivity

Acknowledgements

This work was financially supported by National Natural Science Foundation of China, grant number 51672194 and 51872210; Program for Innovative Teams of Outstanding Young and Middle-aged Researchers in the Higher Education Institutions of Hubei Province (T201602), Natural Science Foundation of Jiangxi Province, China (Contract No. 20181BAB216006), Key Program of Natural Science Foundation of Hubei Province, China (Contract No. 2017CFA004) and the China Scholarship Council (CSC) (No. 201808420278).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by China Scholarship Council: [Grant Number 201808420278]; Hubei Technological Innovation Special Fund: [Grant Number T201602]; National Natural Science Foundation of China: [Grant Number 51672194 and 51872210]; Natural Science Foundation of Jiangxi Province: [Grant Number 20181BAB216006].